Sari 85 (Linum usitatissimum L.) linseed variety was used in this study. Linseed was cultivated at 2008 (LS-08) and 2009 (LS-09) without fertilizer. In addition, at 2009 diammonium phosphate [(NH 4 ) 2 HPO 4 ] and ammonium nitrate (NH 4 NO 3 ) were applied (LSF-09). The linseeds were analyzed for protein, ash and oil contents and fatty acid compositions. There were differences among harvesting years for oil, protein and ash contents of the seeds. The greater oil and protein contents were obtained during LS-08 compared with LS-09. There were no significant difference in protein and ash content between LS-09 and LSF-09 while a significant difference was observed in oil content. Seed protein, oil and ash contents were significantly affected by the harvesting year, but only oil content was affected by the fertilizer treatment. There are significant differences in palmitic, stearic, oleic, α-linolenic and arachidic acid between LS-08 and LS-09. While palmitic, stearic, oleic acid decreased, α-linolenic and arachidic acid increased during 2009 harvesting year. LSF-09 has the highest amount of α-linolenic acid. The fertilizing treatment seems to have an increasing effect on the amount of α-linolenic acid, while it has a decreasing effect on the oleic acid content. © 2010 Springer Basel AG.